An array substrate of an organic light emitting diode (OLED) display device comprises a plurality of sub-pixels, each of the sub-pixels being provided with an organic light emitting diode for emitting light of a corresponding color, the organic light emitting diode comprises a cathode, an anode, a light emitting layer, and may also have a hole transport layer, a hole injection layer, an electron transport layer, an electron injection layer etc. Wherein, the materials of the light emitting layers of the sub-pixels of different colors are different, so their luminous efficiency and life time are also different. Generally speaking, the existing green light emitting layer has the highest efficiency and the longest life time, while the blue light emitting layer and the red light emitting layer have a relatively bad efficiency and life time (wherein the blue is generally the worst).
In the existing array substrate, the sub-pixels of respective colors are all rectangle of the same size; the array substrate in this form has a simple structure which is clear and neat, however, wherein the red sub-pixels and the blue sub-pixels (actually the light emitting layers therein) have relatively short life times, when their performances are degraded or damaged, the green sub-pixels are usually still in good condition, thereby rendering the whole life time of the array substrate to be relatively short, such that the performance of the green sub-pixels cannot be utilized sufficiently.